The objective of this study is to determine potential predictors of suicidal behavior from baseline biologic, psychiatric and psychosocial variables after a 1 year follow-up. This study will also determine whether attempt characteristics (e.g., number of past suicide attempts and type of current suicide attempt) (e.g., violent versus non-violent) seriousness of intent and degree of medical damage are related to serotonergic function, as assessed by the prolactin response to fenfluramine challenge.